Electric current interrupter



May 3, 1932 l.. LUDWIG 1,856,878

ELECTRIC CURRENT INTERRUPTER Filed Nov. 5, 1930 INVENTOR. o u/.s l. volw/g @my jim@ A TTORNE Y.

Patented May 3, 1932 PATENT OFFICE LOUIS LUDWIG, OF BROOKLYN, NEW YORK ELECTRIC CURRENT INTERRUPTER Application led November 3, 1930. Serial No. 492,996.

The invention relates to interrupters of the type which is inserted in a lamp socket and which causes the current in the lamp, or other device inserted in the socket, to be interrupted B at regular intervals. It has for one object to provide a device of very simple construction, consisting of few parts which are in expensive to manufacture and easy to assemble. Another object is to provide an interrupter which may be used in either the screw type socketor in the so-called bayonet-joint socket. A further object is to so construct the device that the bi-metallic element employed therein is neither bent or otherwise distorted,

thereby assuring greater accuracy of operation.

These and other objects and advantages will be readily understood from the accompanying drawings of certain preferred embodiments in which, however, certain modifications might be made without departing from the scope of the invention. In the dra-win s i(Fig. 1 is a plan view of one embodiment of the improved interrupter shown with the contact cover removed,

Fig. 2 is a cross-sectional side view of same,

Fig. 3 is a plan view of another embodiment of the interrupter,

' Vv30 Fig. 4 is a cross-sectional side view of same,V Fig. 5 is a side elevation of the interrupter shown in Figs. 3 and 4 and illustrating its dual utility, and

Figs. 6, 7 and 8 show certain modifications of various details of the interrupter.

Referring first to Figs. 1 and 2, the device consists of an insulating body member 10 which is preferably disc shaped and which is moulded with a vcircular recess 11. A concentric groove 12 is formed at the top edge of the recess and in this a dome-shaped, metal cover 13 is tightly secured. A tongue 14 is formed on the cover and fits in a seat 15 moulded in the body member. A thermostatic element 16 is contained within the recess and held securely in the seat 15 by the tongue 14.

. p0 18, upon which a resistance wire 19 is wound.

A contact point 20 is attached to the free end of the strip 17. It co-acts with a contact point 21 which is secured in one end of a metal connector 22. This connector is secured in the bottom of the recess by means of an eyelet or rivet 23. One end of the resistance wire is connected to the tongue 14 while the other end is connected to the connector 22.

The size of the device is suoli that it will 't inside and be centered in a standard, elec- G0 tric, lamp socket. Vhen it is placed in such a socket and a. lamp is inserted, the head of the rivet 23 engages with the center contact of the socket while the cover engages with the center contact of the lamp. When a cur- G5 rent is turned on it will flow through the rivet 23, connector 22, resistance wire 19, cover 13, and hence through the lamp.

The heat given ofi by the resistance wire causes the bi-mctallic strip to curve until the contacts 20 and 21 touch, after which the current is shorted through the bi-metallic strip. lVhen the resistance wire cools the strip straightens out and the current is again switched through the wire. It is evident that T5 the light in the lamp is dimmed while the current flows through the resistance wire and bright while lowing through the metal strip. According to the dimensions of the bi-metallic strip and the amount of resistance in the so wire employed, the interruptions will be more or less frequent and of longer or shorter durations.

ln the device shown in Figs. 3, 4 and 5, `provisions have been made so that it may be employed not only in screw type sockets but in bayonet-joint sockets as well. To accomplish this the cover is provided with two openings 24 and 25 through which the prongs 23 and 27, of a bayonet-joint socket 28, may 90 pass. A hole 29 is also provided in the bottom of the recess 11. While the hole 29 is of just sufhcient size to allow the prong 26 to slide therein, the hole 24 is made large enough to prevent any contact between the prong and the cover.

rEhe opening 25 is made by stamping and forming a plurality of contact Springs 30 which, while firmly engaging with the prong 27 still allows it to slide between them. The 100 prong 27 does not pass through the body member but stops against the bottom of the recess 11. A metal connector 31 is secured by the rivet 23 in such a position that a stud 32 secured on the end thereof is exactly located in the place where the end of the prong 27 kvyould be if it passed through the body mem- In this embodiment the current passes through stud 32, connector 31, rivet 23, connector 21, resistance wire 19, cover 13, springs 30 and hence through the prong 27 and the lamp. The action of the thermostatic element is the same as previously explained.

Fig. 5 illustrates how the device may be used in either type of socket. When used in the screw-type socket, the rivet 23 engages on the Socket contact 33 while the cover 13 engages with the lamp contact 34. When used in the bayonet socket, the prong 26 engages on the socket contact 35 while the stud 32 engages on the socket contact 36. As the springs 30 exert a certain amount of friction on the prong 27 and as the prong 26 fits fairly tight in the hole 29, the interrupter may be attached on the lamp before this is inserted in the socket. This is a distinct advantage as it is difficult to align the parts if the interrupter is iirst inserted in the socket.

In Figs. 6, 7 and 8 modifications of construction are'shown. In this case a single member 37 has been substituted for the connector 22, rivet 23, connector 31 and stud This member is moulded in the body member. Its corresponding parts have been numbered as in the other views and its shape is plainly shown in Figs. 6 and 7, Fig'. 6 showing a side view of the member moulded in the bodyl member and Fig. 7 showing a bottom view of the member itself. In Fig. 8, the tongue 14 on the cover 13 has been made longer and bent ina U shape. The thermostatic element is securely clamped-in this bend.

From the foregoing it will be seen that I Y have provided a device of the simplest constructionv which can be employed in either of the sockets mentioned, and in which the bimetallic member is not bent or otherwise distorted. This is important, because, when Vsuch is the case, the metal must be specially cured over said recess and constituting one terminal of the device, al thermostaticallyoperated switch lever secured under and electrically connected with said cover, and a coacting switch 'member securedin the bottom of the recess and having means 'which extend through the bottom wall of the recess and which constitutes the other terminal of the device.

2. A current interrupting device comprising an insulating body member insertable in an electric lamp socket, a recess formed in one face of said body member, a cover which forms one terminal of the device secured over said recess, a thermostatically-operated switch lever secured to and electrically connected with said cover, and a co-acting switch member partly contained in the bottom of the recess and partly extending through the bottom'wall of same to form the other terminal.

3. A current interrupting device comprising an insulating body member insertable in a bayonet-joint lamp socket, a recess formed in one side of said body member, a metal cover secured over said recess, a thermof statically-operated switch lever secured by and electrically connected with said cover, a co-acting switch member secured in the recess and having a connecting member extending through the bottom wall of the recess to contact with one terminal of the socket in which the device is inserted, an opening formed in said cover through which one prong of the lamp to be inserted in the socket willl pass while being electrically connectedwith the cover, and aligned openings formed in the cover and the body member through which the other prong of such lamp will pass without contacting with the cover.

Li. A current interrupter comprising an in-0 sulating body member insertable in a bayonet-joint lamp socket, a recess formed in one side of said body member, a metal cover secured over said recess, a thermostatically-` `operated switch lever' sec'ured under said cover and electrically connected therewith, a co-acting switch member secured in the recess and having a connecting member extending through the bottom wall of the recess to contact with one terminal of the socket in which the device is employed, an opening formed in said cover through which one prong of the lamp to be used in the socket will pass, resilient members associated with said opening for providing slideable electrif cal contact between said prong and the cover, and aligned openings formed in the cover and the body member through which the other prong of such lamp may pass without contacting with the cover.

5. A current interrupter comprising an insulating body member containable in a vbayonet-joint lamp socket, a recess formed in one sid-e of said body member, a metal coverse-l cured lover said recess, a thermostaticallyoperated switch lever secured under said cover yand electrically connected therewith, a coacting switch member secured in the recess and having a vconnecting member extending through the bottom wal-1 of the recess to `contact with one terminal of the socket in which the device is employed, an opening formed in said cover through which one prong of the lamp to be used in the socket will pass, resilient members associated with said opening for providing slideable electrical contact between said prong and said cover, aligned openings formed in the cover and the body member through which the other prong of such lamp may pass without contacting with the cover, and said resilient members and the opening in the body member constituting means whereby the device may be rictionally held on the said prongs prior to their insertion in the socket.

6. A current interrupter comprising an insulating body member insertable in a lamp socket, a recess formed in said body member, a cover secured over said recess and forming one contact for engagement with the center terminal of a lamp inserted in the socket, a thermostatically-operated switch lever secured to and electrically connected with said cover, a co-acting switch member secured in the recess, said switch member having one contact extending through the center of the bottom wall of the recess for engagement with the center terminal of a screw-type socket and another contact extending through said wall to one side of the first-mentioned contact for engagement with one of the terminals of a ayonet-joint socket, aligned openings formed in the cover and body member through which one prong of a bayonetjoint lamp may pass without contacting with the cover, and an opening formed in the cover through which the second prong of such lamp may pass while electrically contacting with the cover.

LOUIS LUDWIG. 

